Rapid Heat- and Light-Responsive Shape Memory Polymer with High Strain as Remote Light-Controlled Actuators Fabricated Via Gamma Radiation

Shape memory polymers can return to their initial shape from a programmed temporary shape under external stimuli, such as light, heat, and magnetism. However, it remains challenging to achieve multistimuli manipulations in one material system. Here, a facile one-step method for fabricating heat and light response shape memory polymer has been developed by taking poly(chlorotrifluorethylene-vinylidene fluoride) (P(CTFE-VDF)) film that suffered gamma radiation directly. During the solid radiation, the cross-linking netpoint and photosensitive moieties were brought into the polymer structure in one step. The degree of chemical crosslinking can be controlled by an absorbed dose of radiation thus providing shape fixity capacity. Combining with the crystalline PCTFE region as the reversible phase of shape memory, the radiated copolymer can obtain a high-strain shape memory effect and as high as 853% recoverable strain. Meanwhile, the unsaturated groups formed by dehydrochlorination during radiation made the color of the copolymer transform from translucent to black, which gives the copolymer a great photo-thermal effect. By the utilization of a near-infrared laser, the radiated P(CTFE-VDF) can be applied to remote-controlled and precise moving of objects at both horizontal and vertical directions by the controlling of light spot position and power density, thus having potential application value on remote light-controlled actuators.